Class Recursive

java.lang.Object

Recursive

public class Recursive
extends Object

Various recursive methods to be implemented. Given shell file for CS314 assignment.

Constructor Summary

Constructors

Constructor and Description
Recursive()

Method Summary

Modifier and Type	Method and Description
static int	canEscapeMaze(char[][] rawMaze) Problem 8: Maze solver.
static boolean	canFlowOffMap(int[][] map, int row, int col) Problem 6: Determine if water at a given point on a map can flow off the map.
static void	drawCarpet(int size, int limit) Problem 5: Draw a Sierpinski Carpet.
static String	getBinary(int n) Problem 1: convert a base 10 int to binary recursively.
static ArrayList<String>	listMnemonics(String number) Problem 4: Find all combinations of mnemonics for the given number. pre: number != null, number.length() > 0, all characters in number are digits post: see tips section of assignment handout
static int	minDifference(int numTeams, int[] abilities) Problem 7: Find the minimum difference possible between teams based on ability scores.
static int	nextIsDouble(int[] data) Problem 3: Returns the number of elements in data that are followed directly by value that is double that element.
static String	revString(String stringToRev) Problem 2: reverse a String recursively. pre: stringToRev != null post: returns a String that is the reverse of stringToRev

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Recursive

public Recursive()

Method Detail

canEscapeMaze

public static int canEscapeMaze(char[][] rawMaze)

Problem 8: Maze solver.
pre: board != null
pre: board is a rectangular matrix
pre: board only contains characters 'S', 'E', '$', 'G', 'Y', and '*'
pre: there is a single 'S' character present
post: rawMaze is not altered as a result of this method. Return 2 if it is possible to escape the maze after collecting all the coins. Return 1 if it is possible to escape the maze but without collecting all the coins. Return 0 if it is not possible to escape the maze. More details in the assignment handout.

Parameters:

rawMaze - represents the maze we want to escape. rawMaze is not altered as a result of this method.

Returns:

per the post condition

canFlowOffMap

public static boolean canFlowOffMap(int[][] map,
                                    int row,
                                    int col)

Problem 6: Determine if water at a given point on a map can flow off the map.
pre: map != null, map.length > 0, map is a rectangular matrix, 0 <= row < map.length, 0 <= col < map[0].length
post: return true if a drop of water starting at the location specified by row, column can reach the edge of the map, false otherwise.

Parameters:

map - The elevations of a section of a map.

row - The starting row of a drop of water.

col - The starting column of a drop of water.

Returns:

return true if a drop of water starting at the location specified by row, column can reach the edge of the map, false otherwise.

drawCarpet

public static void drawCarpet(int size,
                              int limit)

Problem 5: Draw a Sierpinski Carpet.

Parameters:

size - the size in pixels of the window

limit - the smallest size of a square in the carpet.

getBinary

public static String getBinary(int n)

Problem 1: convert a base 10 int to binary recursively.
pre: n != Integer.MIN_VALUE

post: Returns a String that represents N in binary. Returend char shall start with a '-', a negative sign, if parameter n is < 0. All subsequent chars in returned String shall be '1's or '0's. Most significant digit is at position 0

Parameters:

n - the base 10 int to convert to base 2

Returns:

a String that is a binary representation of the parameter n

listMnemonics

public static ArrayList<String> listMnemonics(String number)

Problem 4: Find all combinations of mnemonics for the given number.
pre: number != null, number.length() > 0, all characters in number are digits
post: see tips section of assignment handout

Parameters:

number - The number to find mnemonics for

Returns:

An ArrayList with all possible mnemonics for the given number

minDifference

public static int minDifference(int numTeams,
                                int[] abilities)

Problem 7: Find the minimum difference possible between teams based on ability scores. The number of teams may be greater than 2. The goal is to minimize the difference between the team with the maximum total ability and the team with the minimum total ability.
pre: numTeams >= 2, abilities != null, abilities.length >= numTeams
post: return the minimum possible difference between the team with the maximum total ability and the team with the minimum total ability.

Parameters:

numTeams - the number of teams to form. Every team must have at least one member

abilities - the ability scores of the people to distribute

Returns:

return the minimum possible difference between the team with the maximum total ability and the team with the minimum total ability. The return value will be greater than or equal to 0.

nextIsDouble

public static int nextIsDouble(int[] data)

Problem 3: Returns the number of elements in data that are followed directly by value that is double that element. pre: data != null post: return the number of elements in data that are followed immediately by double the value

Parameters:

data - The array to search.

Returns:

The number of elements in data that are followed immediately by a value that is double the element.

revString

public static String revString(String stringToRev)

Problem 2: reverse a String recursively.
pre: stringToRev != null
post: returns a String that is the reverse of stringToRev

Parameters:

stringToRev - the String to reverse.

Returns:

a String with the characters in stringToRev in reverse order.